The present disclosure relates to subject matter contained in priority Japanese Patent Application No. 2001-174432, filed on Jun. 8, 2001, the contents of which is herein expressly incorporated by reference in its entirety.
1. Field of the Invention
The present invention relates to a compressor with a build-in electric motor which is suitable to be mounted on a mobile structure such as a motor vehicle. The invention also relates to a mobile structure having such a compressor.
2. Description of Related Art
In a vehicle driven only by an engine, a compressor driven by the engine has been used for air-conditioning the vehicle compartment with the compressor being mounted alongside of the engine.
Hybrid vehicles having both an engine and an electric motor and traveling by use of one of them according to conditions have been practically used for going on public roads. Air-conditioning of the vehicle compartment of this hybrid vehicle is made by a compressor driven by the engine in the same manner as conventional engine-driven vehicles, which compressor is mounted alongside of the engine.
It is proposed that the engines of hybrid vehicles should be shut off while they are temporarily stationary at a place such as a traffic light in order to reduce effects of the engine upon the environment. When the proposal is followed with a vehicle where a compressor driven by the engine is used, air-conditioning stops each time when the vehicle stops, causing problem for the driver and passengers in the compartment in summer and winter seasons, and especially in regions with extremely cold or hot climate.
For solving such a problem, there is an idea of adopting a compressor to be driven by an electric motor, especially a compressor to be used for air-conditioning in a building as shown in FIG. 7. The compressor with a built-in electric motor is housed in a container 102 made of iron, together with a compression mechanism 100 and an electric motor 101. In the hybrid vehicle, furthermore, the arrangement of devices in an engine room is based on that of the conventional motor vehicle. Thus, there is no space or location for installing the conventional compressor with the built-in electric motor for air-conditioning in the building in the engine room, so that the compressor should be mounted alongside the engine.
Regarding such a problem, the present inventors have conducted various experiments and found the following facts. That is, there is an inconvenience that a mounting leg or mounting seat 103 made of a sheet-metal welded on the container 102 requires a seat on the engine side. In addition, the compressor is heavy as much as about 9 kg or more. As the compressor is mounted alongside the engine, the strength of the mounting seat 103 is insufficient with respect to the weight of the compressor and vibrations thereof. In addition, the compressor is forced to receive vibrations of the engine, so that a weld zone between the conventional mounting seat 103 and the container 102 may be fractured, resulting in poor durability and lack of reliability. There is also an idea to prevent the influence of vibrations of the engine to the compressor and to the vehicle compartment by sandwiching an elastic member between the mounting seat 103 and the engine. However, the mounting position of the mounting seat 103 to the engine is greatly varied, so that the position on which the elastic member is to be mounted can be also varied. It results in the increase in the number of components and also the increase in the number of fabrication steps, causing the increase in costs. Furthermore, the elastic member arranged on each of the mounting parts exerts its ability of impact absorption on a restricted area on the mounted part, resulting in poor vibration control. If the vibration control is compensated using any member having a small spring constant, the elastic member tends to be broken between the vibrating engine and the compressor.
Furthermore, the conventional compressor with the built-in electric motor has large axial dimensions. For example, the container 102 extends to approximately 250 mm. That is, a discharge port 104, a suction port 105, inner and outer electric connection parts 106, and the mounting legs 103 are longitudinally extended from both ends of the container 102. In addition, the driving shaft 107 is supported by main- and sub-bearing members 108, 109 independently installed in the container 102 together with the both ends of the driving shaft 107 connected to the electric motor 101. In addition, the driving shaft 107 actuates a pump 110 for oil supply being provided independently from the container 102 on the side of the sub-shaft bearing member 109. Such a complicated construction of the compressor is hardly incorporated in an electric-powered vehicle which has been only realized in a small-sized vehicle.
Simultaneously, the conventional compressor with the built-in electric motor is made of iron, so that the total weight thereof is about 9 kg or more. Thus, it becomes a problem in realizing the high speed and the energy saving because of the increase in driving load when it is mounted on the mobile structure.
On the other hand, as shown in FIG. 8, there is provided a compressor with a built-in electric motor in which a container 120 is made of an aluminum material to reduce the weight of the container 120. In this case, however, the principle configuration of the container 120 is substantially the same as that of the container 102 made of iron except that the axial length of the container 120 is approximately 220 mm which is slightly smaller than that of the container 102. In addition, just as in the case with one shown in FIG. 7, the container 120 is constructed of three container members 120a-120c by which two independent connection portions 121 are formed on the body. Those shown in FIG. 7 are made of iron and are mutually connected to each other by welding under favor of being designed as maintenance-free without overhaul. However, the container members made of aluminum as shown in FIG. 8 are not suitable for welding, so that they are connected to each other by means of bolt connection. The wall of the aluminum container 120 in the thickness directions is greater than that of the iron container 102 to satisfy the conditions of a pressure container. For the connection with bolts 122, a pair of flange portions 123 in each of the two connection portions 121 is required. Here, the flange portion 123 is protruded outwardly from the periphery of the container 120 in the radial direction. In addition, the flange portion 123 continuously or discontinuously extends around the container 120 in the circumferential direction. In each connection portion 121, a lot of bolts 122, for example eight bolts 122, may be used so that the total weight of the container 120 is approximately 8 to 9 kg. It means that the substantial reduction in the weight of the container 120 is not achieved.
It becomes urgent business to provide a small-sized and lightweight compressor with a built-in electric motor now in a tendency of planning an electric operation of various kinds of load by using a working voltage of 42 volts in a gasoline-powered vehicle, a hybrid vehicle, or an electric-powered vehicle.
An object of the present invention is to provide a small-sized and light-weighted compressor with a built-in electric motor.
To achieve the above object, a first aspect of the invention is to provide a compressor with a built-in electric motor, where a compression mechanism and a built-in electric motor for driving the mechanism are housed in a container. In the container, a suction port, a discharge port, inner and outer electric connection parts, and mounting legs are provided on the same side of a body of the container.
According to the above configuration, the entire size of the compressor in the axial direction is reduced till it becomes almost equal to the size of the container in the axial direction. In addition, such a concentrated arrangement of structural components on the predetermined area of the container prevents them from taking up much space, compared with the arrangement of structural components dispersed around the container. As the suction port, the discharge port, the electric connection parts, and the mounting legs are arranged in a restricted area so as to be close to each other to share a part of or the whole of the wall of the container in the thickness direction. Thus, the section of the container on which each of them dominantly arranged is reduced. In addition, since the suction port and the discharge port are positioned on the body of the container, a margin for connection of an external pipe is obtained on the internal diameter side by utilizing the fact that each of the outer and inner peripheries of the end of the container tends to become a dead space. The wall of the container in the thickness direction is shared much more, compared with the case of outwardly extending from the container, so that the reduction in size and weight of the container is achieved. The bulk of the container is further reduced as much as the extent of both the suction port and the discharge port which do not protrude out of the container. Consequently, the compressor with the built-in electric motor is made compact and light weight in addition to allow the reduction in cost. Thus, the compressor is easily mounted on the mobile structure such as an automobile and contributes to energy saving.
A second aspect of the invention is to provide a compressor with a built-in electric motor, where a compression mechanism and a built-in electric motor for driving the mechanism are housed in a container, including: a bearing part for supporting an end of a driving shaft for driving the compression mechanism, the bearing part which is formed on an end wall integral to a body of the container, where the end of the driving shaft to be supported by the bearing part is located in the direction opposite to the compression mechanism and the driving shaft is connected to the built-in electric motor; a pumping mechanism provided in a pumping chamber opened to an external surface of the end wall, which is connected to the end of the driving shaft in the direction opposite to the compression mechanism; and a closing member that closes the opening of the pumping chamber.
In such a configuration, the bearing part of the driving shaft on the side of the pump mechanism and the pump mechanism portion are assembled and concentrated in the end wall of the container. Such a concentrated arrangement prevents them from taking up much space, compared with the arrangement of structural components dispersed around the container. In other words, they are arranged in a restricted area so as to be close to each other to share a part of or the whole of the wall of the container in the thickness direction. In addition, they share a part of or the whole of a space in the container in the axial direction, so that the specific section and the specific space in the container are reduced. Thus, the size of the container is reduced in the axial direction. Furthermore, reduction in weight of the whole is achieved as much as reducing the specific section of the container and the axial size of the container. Consequently, the compressor with the built-in electric motor is made compact and light weight in addition to the reduction in cost. The compressor is thus easily mounted on the mobile structure such as an automobile and contributes to energy saving. Furthermore, since a positioning of the bearing and the container becomes unnecessary by integrating the bearing part of the driving shaft into the end wall of the container, the positioning accuracy is increased while an assembling operation becomes ease, thereby reducing the cost.
While novel features of the invention are set forth in the preceding, the invention, both as to organization and content, can be further understood and appreciated, along with other objects and features thereof, from the following detailed description and examples when taken in conjunction with the attached drawings.